A liquid-crystal display apparatus has a liquid-crystal panel unit and a backlight unit. The liquid-crystal panel unit has a plurality of liquid-crystal devices. By the control of voltage to be applied to the respective liquid-crystal devices, the transmittance of the respective liquid-crystal devices is controlled. The voltage to be applied to the respective liquid-crystal devices is determined according to a gradation value of image data. The backlight unit is provided on the back-surface side of the liquid-crystal panel unit. Light from the backlight unit is modulated when passing through the respective liquid-crystal devices. Thus, an image is displayed on a screen.
However, in a case where uneven stress is applied to a member supporting the liquid-crystal panel unit, the orientation of the liquid-crystal devices (liquid-crystal molecules) is partially disordered without the application of voltage to the liquid-crystal devices. Therefore, the transmittance of the liquid-crystal panel unit does not become uniform even if a gradation value of image data is uniformly set, which results in the display of an image with unevenness (brightness or color unevenness). Such display unevenness (brightness or color unevenness on a screen) is particularly conspicuous in a case where a gradation value of image data is small. Specifically, in a case where a gradation value of image data is small, display unevenness in which display brightness (screen brightness) is partially high is conspicuous. In addition, such display unevenness occurs also in a case where a black image entirely colored in black is displayed. Therefore, such display unevenness will be described as “black display-unevenness” below.
As technology for reducing display unevenness, technology disclosed in PTL 1 has been proposed. According to the technology disclosed in PTL 1, an offset value is added to input image data.
Further, as technology relating to a liquid-crystal display apparatus, technology disclosed in PTL 2 has been proposed. According to the technology disclosed in PTL 2, a plurality of light sources is used as the light sources of a backlight unit. Further, the light-emission brightness of the plurality of light sources is individually controlled based on the brightness of image data, and the image data is corrected based on the light-emission brightness of each of the light sources. By the technology disclosed in PTL 2, the contrast of a display image (image displayed on a screen) can be increased.